Tympanometry Flashcards
What is the purpose of Tympanometry?
To identify and measure the dynamic compliance of the TM and ME performance.
Requires an intact TM, the presence of air in the ME space and functioning ET that is within normal limits of range. Requires all bones, muscles, tendons and ligaments of the ME to be present, intact and functioning. General range of static compliance runs 0.4cc-1.6cc of equivalent volume
Type A Tymp
Requires the same functionality requirements of Type A except the transfer of energy is somewhat impeded by an increased stiffness. Still has an identifiable peak but static compliance measurement is markedly reduced ranging up to 0.4cc—can be caused by ossicular fixation, tympanosclerosis, or scar tissue on ED
Type As or Shallow A Tymp
Require an intact TM as well as normal ET function.Resistance to flow of energy is smaller than normal. Static compliance measures identified in these cases fall above 1.6cc of equivalent volume. Some causes of this Tymp type are ossicular discontinuity , monomeric membrane or recovering perforation, cases of abuse
Type Ad Tymp
This Tymp type can be caused by obstruction of the canal, perforation of TM, ME fluid, infection, over retraction of the TM, Otitis Media
Type B Tymp
This type of Tymp is usually seen when the ear is in Transition or in recovery mode. When Middle ear muscle reflexes may not be present. Medical Referral is required with this type.
Type C Tymp
The probe when conducting Tympanometry consists of 3 holes-
- A tiny speaker- admits tone into EC
- An air pump- the way to changed air pressure
- A tiny Microphone- that picks up the sound that is reflected off of TM
What are the 4 measurements that helped us to read and classify a tympanogram
- Physical Volume (Vea) AKA ECV or Ear canal Volume
- Static Compliance (Ytm)
- Peak Pressure (TPP)
- Width (TW)
Physical Volume is…and is also known as…
Measurement of the volume of air in front of the probe in cubic centimeters (cc) or millileters (mL) when the ear canal is pressured to +200daPa
Also known as Ear Canal Volume ECV
Static Compliance is
Also known as Static Admittance.
Is basically the height or peak of the Tymp. It is measured in millimhos (Mmho) or milliliters (mL)
Peak Pressure is…
Is the pressure at which the peak or static compliance occurs. Identified in daPa and can be seen along the x axis of the Tympanogram. Allows us to determine if the pressure in the ME is positive or negative compared with pressure of the EC
Width is…
The measurement in daPa at half of static compliance of the peak to the compliance at +200 daPa
Tymp with normal peak height, pressure and ECV
Type A
Tymp with no peak and is flat, ECV is normal in cases of Otitis Media with Effusion, ECV will be larger in cases where there is a perforation of TM or if tubes have been put in, ECV will be low in cases of impacted wax or foreign body is in canal
Type B
Normal Peak height, but reduced peak is also possible, Negative peak pressure, Normal ECV
Type C
